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85 K5 fouling plugs

R

rvest1

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Davison, MI
I have a 1985 K5 Blazer. 350 -w- bigger Cam, Quadra-Jet Carb. 700R4, 4.11 Rear Full Floater. 38.5 TSL SS Radials on Rear, 36 Mickey Thompsons on Front. I just received this Blazer in a trade. It came with 3 38.50s and 1 44" groundhog. I got some used 36s and put them on the front and took 4 1/2 inches of body lift off (leaving 3" of body lift still on. The guy said that he recently rebuilt the carb. The first time I saw it, it would not start. We put new plugs in and it started right up. The electric choke is not hooked up to power and I do not know which wire to use yet. Anyhow, it is quite cold outside here in MI and I went out last week and it started right up. I let it run for a bit and then shut it down. Then I went out yesterday and it would not start. I have never had a carbureted vehicle before (several Fiero's, several cherokee's, wranglers, and late 90's trucks) so I am not sure if I should pump the gas or what. Thing is that after several minutes of trying this and that, the battery died. I took the plugs out and they were all soaking wet with fuel.

How to I unflood it or will it do that itself?
It has ACDelco R44TS Plugs, should I use something else? Hotter plugs maybe?
Should I adjust the air/fuel mixture screw? If so how many turns from closed should I put it?

I do not know the cam size or brand and have never dealt with a cam before. This truck origionally came with a 305 and the 350 was put in a couple years ago supposedly.

If I spray ether (starting fluid) into the carb, where should I spray it?

Any info could help. I am going back to college and am strapped for cash between tuition, child support and rent but the navy sends me a GI Bill check every now and then so maybe I can come up with a little money to buy some parts but I need to know exactly what I need. When it started last week it idled perfect and revved great. The guy said it had close to 400HP but who knows. I want the best fuel economy I can get.
 
With a QuadraJet, the proper way to start it (assuming it's decently tuned) when it's cold, is to take it all the way to the floor twice, then just barely crack the throttle. All the ones that I have built start very easily if you follow this, even the ones without a choke.

First things first, you need to get the choke hooked up and make sure it works. It'll foul the plugs all the time if that choke doesn't open the way it should.

If this is your first carb'd vehicle, you are in for a HUGE learning curve. One thing to remember, the accelerator pump of a Q-Jet is WAY oversized for anything but a 500CID plus motor. If you keep pumping and pumping, you'll flood it out everythime. Two pumps when it's cold, and maybe one if it's been sitting for long enough for the motor to cool off after being driving should do it. Anymore, and you're just wasting fuel.
 
Okay I will definately try that. Should it start right up or need a bit of cranking. Do I have to replace plugs with new ones every time or is there a way to unflood it and/or clean the plug? What plugs should I use?
 
Wow, talk about technical. Math is something I am good at and can respect. I went out and got some R45TS Delco plugs and put them in. Gave 2 pumps of throttle and turned the key. Started right up and ran great. After a couple minutes I openned the choke valve (disabling the choke)by sticking something to keep it open (electric choke was not wired when I got it. Tried to drive it and apparently the thing I put it there to keep the choke open (spark plug) came out and it shut down. I tried to start it and it started right up but shut off when I hit throttle. Openned hood and stuck a screwdriver in there. Started but Idled really f***ing high. Scared the hell out of me. Spent 10 minutes wiring a switch to the battery and to the electric choke. Hit the switch and waited for choke to open. After a couple minutes it was open. Turned key and started right up.

Drove back to my parking spot and started trying to get the back window to roll down. When I hit the button I can hear it engage but will not roll down. More stupidly than everything else I had done I wired the window switch open and tried to roll it down while pressing against it. When I pushed too hard on it PPshhhhhhttttt it shatterred. Now it is snowing and I have no tailgate window. WOW wish I had money for that; I guess I will have to find a cheap tarp or plastic wrap to cover it from the snow until my GI Bill sends me my tuition check so I can buy a new rear hatch window.

Anyway the Quadra-jet carb is stamped 78 on the side. Does that mean that it is from a 78 model year truck? If so does that mean that my engine is the same? The guy I got it from a few weeks ago said it was not the stock engine (came with a 302). I guess back out to clean the glass out of my truck. My apartment people are going to complain about this for sure.
 
Ok, it came with a 305, the only GM 302 was made in the late 60's. There should be a long number, on the drivers side of the Qjet, starting with either a 7 or 17. Probably starting with a 17, as most I find running now a days are.

The switch you've got wired to the choke can be removed, but use a fuse in the line and pull the power from a circuit that is only live when the switch is in the run position. There should be a green wire on top of the engine on the passenger side that will follow this criteria that is the original choke wire. (pretty sure it is green, I'd go look at my 84, but there's about 10" of snow on the hood right now and it's cold...)
 
Alright i will check it out. Know a good place to find rear glass or an entire rear door for cheap??
 
If the brotherhood here cant find one for you cheep in the area check out www.car-part.com. It is a fairly decent junk yard search engine. looks like rear glass is going for $40 - $150 in MI. Not sure where you are exactly but it is worth a shot.

Cheers,
Rufus
 
TerryD said:
Ok, it came with a 305, the only GM 302 was made in the late 60's. There should be a long number, on the drivers side of the Qjet, starting with either a 7 or 17. Probably starting with a 17, as most I find running now a days are.

The switch you've got wired to the choke can be removed, but use a fuse in the line and pull the power from a circuit that is only live when the switch is in the run position. There should be a green wire on top of the engine on the passenger side that will follow this criteria that is the original choke wire. (pretty sure it is green, I'd go look at my 84, but there's about 10" of snow on the hood right now and it's cold...)
Click to expand...

My number is 17059206 and from short research I have found that it is from a 79 Chevy C10. Is that okay for my 85 K5. Both are 350s. Maybe my engine is from the same year and make. My Vacuum lines are everywhere and only a few are even connected. That has to be a problem. Well I guess I will try and figure that out next
 
Yeah, it's definitely a problem. If you can find the original service manual for it, it will have a vacuum hose routing on it.

That is probably a good carburetor for your truck, I'd have to take it apart myself to see what options it has. It's off a truck, which is a good start. Very few truck carburetors had the secondaries travel limited. It is ~810CFM flow rated, and should be "jetted" about right. The electric choke is also a plus, as that makes intake swaps easier and gives you a few more choices.
 
Alright well I got it running nicely at idle and what not. After driving for like 30 feet it wants to die when I let off of the gas. I do not know the vacuum setup for all of it. The back of the carb has a metal vacuum line that goes to the brake booster. I think the air cleaner hooks in just above that. I have 2 lines that are sucking like crazy that I am not sure where they go but they come out of the intake manifold between the carb and distributor on a little tower. I have a giant black orb that has a line coming from it that has a T splitter with one going into the interior and one going to the aforementionned tower. There is a connection in the front top of the carb that has a little clear line (about 1" long and a screw plugging it. There is a line coming from the driver side firewall but I do not know where it goes. There is a line coming from the trans that I do not know where it goes. I do not know where the EGR Valve is located. Basically I am lost and have no money for a manual (though I have heard that manuals do not explain Vac lines anyway). This thing is killing me. The idiot I got it from didn't even have an air filter in it (just open carb, he said he just rebuilt it). I wired the electric choke properly and now it starts first try every time and idles fine. All I know is that it came with a 305, it now has a 350 with a built cam. Any help with Vacuum lines would be appreciated. Charcoal cannister has about 7 hookups and only 2 being used.
 
Well, this appears (not 100% sure)to be the schematic for your truck. shows where each vac line goes. Identify all your parts and just make sure that all the vac lines are there. If you cant identify your parts then post of some detailed Engine compartment pics and the brotherhood should be able to identify the parts. Hope this helps.

Rufus

Removed Image as it was incorrect for the application. Check the radiator core support for your diagram.
85_28L_auto_vac_sch.gif
 
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even if you can't figure out where all the lines go at the moment, at least plug up all vacuum leaks so you can get it running right, then work on other things alittle at a time or whatnot.
 
thing is that all vacuum lines were plugged in one way or another, it idles and rev.s fine until I try to drive it. Could there be another issue other than the vacuum lines? Also brakes are mushy but work, does that mean anything?
 
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